Jimh Posted March 12, 2009 Share Posted March 12, 2009 Go on then. I'll admit to my inexperience on this matter. Discuss... Quote Link to comment Share on other sites More sharing options...
0 xsk460 Posted March 12, 2009 Share Posted March 12, 2009 Best way to do it is give it a go!!! :drive: I painted in the netural positions in red on the gate of my explorer to make more sence of it all! Quote Link to comment Share on other sites More sharing options...
0 xsk460 Posted March 12, 2009 Share Posted March 12, 2009 Just avoid messing a gear change up- or you might end up having to stop, and then set off all over again!:argh: Quote Link to comment Share on other sites More sharing options...
0 Grasshopper Posted March 12, 2009 Share Posted March 12, 2009 Have someone sit next to you with a fire extinguisher. Every time you get one wrong, you get squirted. Thats how I was taught to drive a WLF box..... You learn very quickly! Quote Link to comment Share on other sites More sharing options...
0 Stormin Posted March 12, 2009 Share Posted March 12, 2009 Jim, Given that the pioneer was designed to haul heavy loads at low speeds, is there any need to use more than a couple of gears during normal driving? I'm thinking with all the torque from the gardner engine, top and one gear below should be enough. Not like a gutless WLF :-( I know some may be concerned about clutch wear, but unladen it shouldn't have too hard a time. Not suggesting you shouldn't master the full selection of course, just for ease of normal driving. Quote Link to comment Share on other sites More sharing options...
0 SV2S Posted March 12, 2009 Share Posted March 12, 2009 When we were trying to master gear changes on our Pioneer we spoke to a veteran who said that his bench mark was that he could roll a cigarette between gear changes!! Quote Link to comment Share on other sites More sharing options...
0 xsk460 Posted March 12, 2009 Share Posted March 12, 2009 If memory serves me correctly... I usually set off in third gear, or if the conditions are right, eg on the downhill, no load, ect, I can do a start in forth with little hassle. Usually its the changes down that get people frustrated!:argh: I remember picking my MK1 Militant up from a spot near Winchester, and having never driven anything 'old, big n british' in anger before, I could have cried after the first 1000 yrds, as I struggled with the AEC crash box. however, after my 300 odd mile trip home, I was an expert!!!:drive: I always try plan my changes well before the event, so as to keep the 'buggy' moving. I've seen and heard of other people murdering there engines right down, when on hills, ect, I suppose mayby their affraid of the gear change!!! :cry: P.S. try to avoid going ballsout in a gear right before a change, and then going for the clutch n stick straight away- I've found theres a lot of drag, especially when things are cold, and on occation when you go to pull the stick it doesn't want to play! The 'rolling a ciggy' bit isn't too far feched either... I think 'big chris' put some footage of me towing him in, on Youtube, and it's only when you listen to the exhaust note of my explorer, as I drive and go for a change up, do you start to realise how long a period of time it takes! Quote Link to comment Share on other sites More sharing options...
0 gritineye Posted March 12, 2009 Share Posted March 12, 2009 Only ever driven an Explorer, but this works for me. Get plenty of practice on quiet roads, traffic is stress, you don't need it! Depending on the gradient, pull away in third or 4th, double de-clutch going up and down, you can skip 5th on the flat. Try to get all gearchanging done at low revs, higher revs mean longer pauses in neutral while the revs die down. Use the rev counter to judge change points, note the revs at which an up change works, and use it every time, take your time, it won't be rushed, it knows best! Changing down on hills can be done but is best avoided, but again, using the rev counter it can be done quite easily with practice. The no stress way to practice your down changes and note the revs is as you approach a junction, this way if you mess it up no one will notice as you can coast to a stop and select the gear at the junction. :cool2: Don't panic, take your time, after a while you will be able to do clutch-less changes all day without thinking.! Quote Link to comment Share on other sites More sharing options...
0 Jimh Posted March 12, 2009 Author Share Posted March 12, 2009 What I struggle to understand is the need to double declutch on the way up if there is a clutch stop. Surely the clutch stop does the work of slowing the gearbox input shaft for you without needing to wait for the engine to slow down? Quote Link to comment Share on other sites More sharing options...
0 Grumpy Posted March 12, 2009 Share Posted March 12, 2009 No but it helps Quote Link to comment Share on other sites More sharing options...
0 6 X 6 Posted March 12, 2009 Share Posted March 12, 2009 What I struggle to understand is the need to double declutch on the way up if there is a clutch stop. Surely the clutch stop does the work of slowing the gearbox input shaft for you without needing to wait for the engine to slow down? Try adjusting/disconnecting the clutch stop off it's drum and see whether it makes much difference. When 'Professor' Johnny Squirrell, a highly experienced ex heavy haulage driver, drove my Scammell he never bothered with the clutch at all once the lorry was rolling. He just did it all by ear and by judging the engine/road speed. I never heard him crunch any gear while using what I called the 'Squirrell' method. As regards anyone mastering a crash gearbox, my time spent running a HGV school in London many years ago (Bedford TK's !) is that all advice and demonstration wasted. We have to get in the driving seat and find out by our mistakes. Quote Link to comment Share on other sites More sharing options...
0 gritineye Posted March 12, 2009 Share Posted March 12, 2009 What I struggle to understand is the need to double declutch on the way up if there is a clutch stop. Surely the clutch stop does the work of slowing the gearbox input shaft for you without needing to wait for the engine to slow down? Disregard the clutch stop, it just complicates things, only use it to get in gear when stationary. when you have learned to change gear without it you can see if it's easier and use it if you prefer. Quote Link to comment Share on other sites More sharing options...
0 Brooky Posted March 12, 2009 Share Posted March 12, 2009 The clutch stop (right at the bottom of the pedal) should only be used when changing up to slow the revs of the engine quicker to make a faster change. Never never never use it on a down change as after all you want the engine revs to rise to match the lower gear. A tip I was told and have used with the gate change gearbox is when changing up pulll the gearstick towards you and changing down push it away, that way it will avoid having to look at the gate. It used to be said that the true mark of a Scammell driver was if he could drive it without the gate!! Joking aside, dont use too many revs in each gear (remember it is flat out at just over 25 or thereabouts) and that you will be in 6th by the time you are doing about 15mph. Again good advice about planning to keep moving, if you stop you have to get through the gears to find third to start all over again. Get out there and practise and then practise some more eventually you wont need the clutch (only to stop and start) Quote Link to comment Share on other sites More sharing options...
0 ArtistsRifles Posted March 12, 2009 Share Posted March 12, 2009 I've never had the fun of trying to drive a Pioneer but if it's anything like driving a Mk 1 Militant then - dredging up memories of 30+ years ago - the procedure was: Changing up Build up road & engine speed till the engine is just starting to race. Hold it there for a few seconds so that everything in the transmission equalizes. Stamp on the clutch and pull the gear lever into neutral. Come off the clutch, count 1001, 1002 then back on the clutch and slot the gear lever into the next gear up. Come off the clutch and carry on. Typically we'd start these beasties off in second gear. Changing down. Slow down until the right road speed is reached for the appropriate gear (I always found when the engine was starting to just labour was about right). Stamp on the clutch and pull the gear lever back into neutral. Come off the clutch and stamp on the throttle so the rpm climbs over 1500 at least then back on the clutch and slot the gear lever into the next lower gear. Come off the clutch and carry on. As xsk460 says mastering the change is a matter of practice and every vehicle is slightly different. Quote Link to comment Share on other sites More sharing options...
0 Swill1952xs Posted March 12, 2009 Share Posted March 12, 2009 What I struggle to understand is the need to double declutch on the way up if there is a clutch stop. Surely the clutch stop does the work of slowing the gearbox input shaft for you without needing to wait for the engine to slow down? :shake::shake::shake: Whaaaat........ My experience with crash boxes and clutch brakes may not stretch as far as Scammells, but the clutch brake is only for stopping the clutch to enable you to get it in gear when the vehicle is stationary. (Unless it's different on Scammells) If you push the clutch down too far while the vehicle is in gear and still rolling........ you will very likely break it as it will try to act like a transmission brake, and they aint designed to stop fourteen tons. This is why the adjustment of them is so critical and it shouldn't work until the clutch pedal is nearly on the floor. When you change gear; you shouldn't press the clutch pedal all the way down. If you chuck it in a neutral position and then use the clutch brake; you will never get a gear all the time I have a hole in my bottom; as you will make things worse by trying to engage a moving gear, against a stationary clutch plate. Only use the clutch brake to engage gears when stationary. Only depress the clutch half to three quarters of the way down to change gear. Better still, try changing gears on the move without using the clutch. You can do this by pushing it into neutral as you release the accelerator , and gently move the gearstick towards the next gear. As the next gears teeth just tickle each other , and that sensation in your hand stops.... just shove it straight into gear......... no noise..... no clutch and a big grin on your face. Give it a go.......it's not that difficult. I do it on the ERF with a Fuller box that I regularly drive. Jus' tryin to be helpful...........:beatenup: Quote Link to comment Share on other sites More sharing options...
0 Stefano Posted March 12, 2009 Share Posted March 12, 2009 I've driven my mates' pioneer a bit and have found that I start off in third on the flat, and use fourth if there's a downgrade. Changing up is a doddle, and I've found that the quicker you move it through the gate the better the change is. You get a feel for the gate and you don't need to look down after a while. Changing down is an art that I've yet to master, but I'm sure that it can be done.... Quote Link to comment Share on other sites More sharing options...
0 Jimh Posted March 13, 2009 Author Share Posted March 13, 2009 Jus' tryin to be helpful...........:beatenup: Yes. Very helpful. That sound you hear is of a penny dropping. Thanks for that. Quote Link to comment Share on other sites More sharing options...
0 Brooky Posted March 13, 2009 Share Posted March 13, 2009 :shake::shake::shake: Whaaaat........ My experience with crash boxes and clutch brakes may not stretch as far as Scammells, but the clutch brake is only for stopping the clutch Jus' tryin to be helpful...........:beatenup: I think you will find that the clutch brake works on the flywheel side of the clutch (if you look at the Scammell gearbox it is remote from the bell housing) and is used for losing engine revs to enable quick up changes. For those of us who have been lucky enough to drive a vehicle with a twin splitter (the finest gearbox ever fitted to a wagon!!) will know that they were fitted with a clutch stop and was only ever used for up changes if you hit the stop when changing down you ended up with a box full of neutrals!! (a real twin splitter driver would of course not be using the clutch anyway to change gear) Quote Link to comment Share on other sites More sharing options...
0 Grasshopper Posted March 13, 2009 Share Posted March 13, 2009 I have to say that half the fun of driving old vehicles is mastering gear changes. Nothing more satisfying than getting it right. My first experience of a crash box was the day I was sent out to drive a vintage Guy Special bus in service for a 9 hour shift. It was a back to front (or chinese) gearbox. Quickly got the hang of that one! (I did have the advantage that it was my dads vehicle and I had been riding around in it since birth, so knew how it should sound. Apparently my left arm even hangs the same way as my dads between gear changes!). The difference on the route between someone who could drive the box and someone who couldn't was about 10 minutes per trip. Quote Link to comment Share on other sites More sharing options...
0 N.O.S. Posted March 13, 2009 Share Posted March 13, 2009 I remember having a Foden 3000 series 8 wheel tipper demonstrator for a day. The guy dropped it off and never said it had a clutch brake. Oh dear, and I'd never come across a clutch brake before, or a twin splitter! It took a while to work out what was going on, but after getting to grips with the twin splitter box the clutch become almost surplus - at the end of the day I really did not want to give that truck back - that box is a wonderful bit of engineering as you say Brooky. Quote Link to comment Share on other sites More sharing options...
0 Jimh Posted March 13, 2009 Author Share Posted March 13, 2009 I think you will find that the clutch brake works on the flywheel side of the clutch (if you look at the Scammell gearbox it is remote from the bell housing) No, the clutch stop works on the gearbox side of the clutch. The drum for the stop is bolted to the output shaft. Swill is correct. If I jump on the clutch pedal in an exuberant fashion and a gear is still engaged then I am trying to stop the gearbox and therefore the rest of the waggon. /slinks off resolving to think about things a bit harder. Quote Link to comment Share on other sites More sharing options...
0 Brooky Posted March 13, 2009 Share Posted March 13, 2009 I know that I am getting a bit old and forgetful but I am 99% convinced that on a Scammell the clutch brake is on the the input shaft of the gearbox after the clutch, at the back of the bell housing. Remember that in a Scammell (whatever model) the gearbox is remotely mounted from the bell housing. The clutch stop is there to slow the flywheel and drop the engine revs quickly to enable faster up changes so that you do not lose road speed whilst changing gear. I know that if you look through any instruction book for a vehicle fitted with a stop the gear changing instruction will be when changing up depress the clutch pedal half way down, engage neutral,clutch up, clutch to the floor (to engage the stop) into the next higheer gear and foot of clutch. There will also be a warning to only depress the pedal half way down when changing down. The reason is that when changing down you need the engine revs to rise to match the road speed in the lower gear, engaging the stop will slow the engine down and defeat the change. Quote Link to comment Share on other sites More sharing options...
0 Jimh Posted March 13, 2009 Author Share Posted March 13, 2009 I consulted both the drivers handbook and the workshop manual. The WM says nothing on the subject and the DH makes a brief mention of double declutching being a good idea. I've just been out to the workshop to make sure I am not going mad or anything and the clutch stop drum is bolted to the output shaft from the bellhousing. This means that when the clutch stop operates as the pedal is depressed the stop is trying to slow the friction plate and output shaft (as well as all the bits fastened to it further down the chain. Quote Link to comment Share on other sites More sharing options...
0 Brooky Posted March 13, 2009 Share Posted March 13, 2009 Think we are talking at cross purposes (I blame senility in my case) We are both right about the clutch stop, what I think we may be confused about is its use. You are right that if you stamped on the clutch you would be in effect trying to stop the vehicle. Hence the need to realise that correct use is very important and when stopping only depress the clutch half way down. The main use however is as I said to enable easy (easier!) gearchanging, and peoplke should be aware of its correct use. Quote Link to comment Share on other sites More sharing options...
0 gritineye Posted March 13, 2009 Share Posted March 13, 2009 (edited) Disregard the clutch stop, it just complicates things, only use it to get in gear when stationary. when you have learned to change gear without it you can see if it's easier and use it if you prefer. The reason why I put it like that is that I too have read in a manual somewhere about using it on up changes. If the gearbox is in neutral at the time the brake is actuated, it will only act on the clutch shaft and gearbox input shaft and the rest of the drive train will still be turned by the road wheels. Think about it, knock it out of gear on a hill and kill the engine, what would happen? This means one would have to half depress the clutch pedal to shift into neutral, then fully depress it to shift into the next gear, this in theory could possibly be helpful, however in my humble opinion, for a novice it would be too much to get a grip of and should be ignored. Having spent 6 months of my yoof driving up and down the soft blue clay haul roads in the bottom of a reservoir in an AEC 690 dump truck, I can say that practice makes perfic we only used the clutch to start and stop, just slipped the gears in all day, even overloaded with the drag from the clay road which sank as you passed over it, although we never broke through the blue clay top. We worked 7am till 9pm, 7 1/2 days a week, the dumpers had the starters and silencers removed so you couldn't hide up quietly out of sight, and if you stalled 3 times or got caught being push started, you were down the road no second chances, Paddy's rules! Top money though! :-D erf change gear.PDF Edited March 13, 2009 by gritineye Quote Link to comment Share on other sites More sharing options...
0 Brooky Posted March 13, 2009 Share Posted March 13, 2009 Ageed with the comment about complicating matters. As with all these things they are only any good if correct training is given. I find this on state of the art vehicles I train drivers on daily. The vehicles can be driven by anybody, but if the drivers are shown how to use all the functions and understand what they are there for then the vehicle will be driven better. A case in point will be driving an automated gearbox in manual when road conditions allow it, or the correct use of the gas pedal to enable a quick get away on roundabouts etc. Quote Link to comment Share on other sites More sharing options...
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Jimh
Go on then. I'll admit to my inexperience on this matter.
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